Campaign performance

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds genuinely useful return-shape detail — the exact metric set and per-link click breakdown — which matters since no output schema exists. It omits pagination/limits for per-link data, keeping it short of a 5.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two sentences, front-loaded with the core action and return contents, then a single usage cue. No filler or redundancy.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a single-parameter read tool with annotations and no output schema, the description covers purpose, return contents, and a use case, which is nearly everything an agent needs. Minor gaps: no pagination behavior for per-link counts and no explicit boundary with sibling reporting tools.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Only one parameter (campaignId) with 100% schema description coverage, including the helpful hint 'from list_campaigns'. The description adds no additional semantics beyond the schema, so the baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description gives a specific verb+resource ('Get a campaign's results') and enumerates the returned metrics (sent, opens, clicks, bounces, unsubscribes, complaints) plus per-link click counts, which is concrete and unambiguous. However, it never distinguishes itself from close siblings like get_campaign or campaign_recipients, so the agent must infer the split.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The line 'Good for "how did last week's newsletter do?"' supplies a clear, recognizable usage context, which is stronger than vague implied usage. It stops short of naming alternatives or stating when NOT to use it (e.g., vs. get_campaign or campaign_recipients).

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.